Rigidity-variable lamellar flexible woven gripper

Abstract

The invention provides a sheet-shaped flexible woven gripper with variable rigidity, and relates to the field of soft robots, the sheet-shaped flexible woven gripper comprises a flexible woven mesh, a tail end support, a plurality of driving wires and a driving device, the center of the flexible woven mesh is fixed on the tail end support, the driving wires are arranged in the flexible woven mesh, and the driving device is arranged on the tail end support. The driving wires are arranged at intervals in the annular direction with the tail end support as the center, one ends of the driving wires are fixed to the outer edge of the flexible woven mesh, and the other ends of the driving wires penetrate through the tail end support and are connected with the driving device. According to the sheet-shaped flexible woven gripper with the variable rigidity, the shape of the gripper can be changed through the driving wires in the flexible state, a gripped object can be wrapped, the rigidity can be enhanced through the variable rigidity, and the gripping force can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of soft robots, in particular to a thin-sheet flexible braided gripper with variable stiffness. Background Art

[0002] The application scenarios of robot grasping are becoming increasingly complex, and grippers are often required to have universal grasping and high adaptability to achieve effective grasping of objects of various shapes and materials. For eggs and fruits in the food industry, or precision components in the electronics industry, traditional grippers lack precise force control and are prone to applying excessive pressure, causing damage to items; for the need to grasp various daily necessities in a home environment, such as tableware, books, and toys, traditional soft grippers have difficulty adapting to objects of different shapes, sizes, and materials, resulting in inconvenient or failed operations; for complex ruins environments, traditional soft grippers have difficulty operating flexibly in narrow and irregular spaces. Current soft grippers face certain limitations in their adaptability to grasped objects and grasping environments. Summary of the invention

[0003] 1. Technical issues to be solved

[0004] In view of the deficiencies in the prior art, the present invention provides a thin sheet-like flexible braided gripper with variable stiffness, which solves the problems raised in the above-mentioned background technology.

[0005] (II) Technical solution

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: a thin-sheet flexible woven gripper with variable stiffness, comprising a flexible woven mesh, an end bracket, a plurality of driving wires, and a driving device. The center of the flexible woven mesh is fixed on the end bracket, the driving wire is placed in the flexible woven mesh, and the plurality of driving wires are arranged in an annular manner with the end bracket as the center. One end of the driving wire is fixed to the outer edge of the flexible woven mesh, and the other end passes through the end bracket and is connected to the driving device.

[0007] Preferably, the flexible woven mesh is formed by alternately weaving a plurality of transverse thin wires and longitudinal thin wires, some of the transverse thin wires or longitudinal thin wires are capillary material thin wires made of hollow capillary variable stiffness material, and the ends of two adjacent capillary material thin wires are connected by silicone tube end joints.

[0008] Preferably, it also includes a stiffness control device capable of changing the stiffness of the capillary material line.

[0009] Preferably, the stiffness control device includes a hot medium source, a cold medium source, a liquid pump, and a recovery container. The hot medium source and the cold medium source are connected in parallel to the liquid inlet of the liquid pump. The outlet of the liquid pump is connected to the head end inlet of the capillary material wire, and the tail end outlet of the capillary material wire is connected to the recovery container.

[0010] Preferably, the end bracket includes a disc and a screw, one side of the disc has a boss to provide space for the movement of the gripper, and the other side is a buckle surface for placing the screw, and the flexible woven mesh is installed in the buckle surface by the screw.

[0011] Preferably, the material of the capillary material thread may be shape memory polymer (SWP) or thermoplastic elastomer (TPE).

[0012] (III) Beneficial effects

[0013] The present invention provides a thin sheet-shaped flexible braided gripper with variable stiffness, which has the following beneficial effects:

[0014] 1. The variable stiffness thin-sheet flexible braided gripper can change the gripper shape and wrap the grasped object by driving the wire in the flexible state, and can enhance the stiffness and improve the grasping force by changing the stiffness.

[0015] 2. The variable stiffness thin-sheet flexible braided gripper uses a drive wire to drive the flexible braided mesh, which can adapt to the shape of the grasped object, reduce the squeezing force on the clamped object, and can adapt to operations in narrow spaces.

[0016] 3. This thin-sheet flexible woven gripper with variable stiffness can change the gripping strength of the woven net by pulling four drive wires, thereby avoiding damage to fragile objects. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a diagram of the flexible braided mesh of the present invention in an open state;

[0018] Figure 2 This is a diagram of the flexible braided mesh of the present invention in a tightened and grasped state;

[0019] Figure 3 It is a partial enlarged structural schematic diagram of the flexible braided mesh of the present invention;

[0020] Figure 4 Schematic diagram of the heat exchange system of the flexible woven mesh of the present invention.

[0021] In the figure: 1 flexible braided mesh, 2 driving wire, 3 end bracket, 4 screw, 5 buckle surface, 6 disk, 7 transverse thin wire, 8 longitudinal thin wire, 9 capillary material thin wire, 10 hot medium source, 11 cold medium source, 12 liquid pump, 13 recovery container, 14 end joint. DETAILED DESCRIPTION

[0022] The embodiment of the present invention provides a thin sheet-shaped flexible braided gripper with variable stiffness, such as Figure 1-4 As shown, it includes a flexible braided mesh 1, an end bracket 3, a plurality of driving wires 2, and a driving device.

[0023] like Figure 1 As shown, the flexible braided mesh 1 is in the form of a thin sheet, the geometric center of the flexible braided mesh 1 is fixed on the end bracket 3, the driving wire 2 is placed in the flexible braided mesh 1, and a total of four driving wires 2 are provided in this embodiment, and the four driving wires 2 are arranged in an annular manner with the end bracket 3 as the center, one end of the driving wire 2 is fixed to the outer edge of the flexible braided mesh 1, and the other end passes through the end bracket 3 and is connected to the driving device. The driving device can be mainly composed of a motor, a winding disk for winding up the driving wire 2, etc. The motor controls the rotation of the winding disk to control the stretching amount of the driving wire 2, and each driving wire 2 is controlled by a separate motor. When in use, the gripper only needs to pull the driving wire 2 through the driving device to realize the wrapping action of the gripper on the grasped object.

[0024] like Figure 2 As shown, the end bracket 3 includes a disc 6 and a screw 4. One side of the disc 6 has a boss to provide space for the movement of the gripper, and the other side is a buckle surface 5 for placing the screw 4. The flexible braided mesh 1 is installed in the buckle surface 5 through the screw 4. Four holes are opened on the disc 6 for the driving wire 2 to pass through. The driving wire 2 can apply force to the flexible braided mesh 1 by passing through the four holes.

[0025] like Figure 3 As shown, the flexible braided mesh 1 is formed by alternately braiding a plurality of transverse thin wires 7 and longitudinal thin wires 8. Specifically, on the basis of the plurality of transverse thin wires 7, the longitudinal thin wires 8 sequentially pass through the transverse thin wires 7 in the longitudinal direction, and at the same time ensure that the two adjacent longitudinal thin wires 8 pass through the transverse wires in opposite ways. Thus, a flexible braided mesh 1 with a certain rigidity in the transverse direction can be obtained. Part of the transverse thin wires 7 or the longitudinal thin wires 8 are capillary material thin wires 9 made of hollow capillary-shaped variable rigidity materials, and the ends of the two adjacent capillary material thin wires 9 are connected by a silicone tube end joint 14. The rigidity of the structure can be changed by passing cold and hot water.

[0026] Specifically, the device also includes a stiffness control device that can change the stiffness of the capillary material thread 9.

[0027] like Figure 4 As shown, the stiffness control device includes a hot medium source 10, a cold medium source 11, a liquid pump 12, and a recovery container 13. A three-way solenoid valve is provided at the inlet of the liquid pump 12 for switching the hot medium source 10 and the cold medium source 11. The hot medium source 10 and the cold medium source 11 are connected in parallel to the three-way solenoid valve at the liquid inlet of the liquid pump 12. The outlet of the liquid pump 12 is connected to the head end inlet of the capillary material thin line 9, and the tail end outlet of the capillary material thin line 9 is connected to the recovery container 13.

[0028] The specific control principle of the stiffness control device is as follows: the liquid pump 12 can inject the hot medium or cold medium of the hot medium source 10 or the cold medium source 11 into the capillary material fine wire 9 made of the capillary material. Under the connection of the end joint 14, all the capillary material fine wires 9 form a passage, so the medium can fill the entire flexible braided mesh 1, thereby changing the stiffness of the flexible braided mesh 1. After the medium transmission is completed, the waste medium is recovered to the recovery container 13 through the outlet of the braided wire. When it is necessary to increase the stiffness of the flexible braided mesh 1, the liquid pump 12 works to pass the cold medium into the capillary material fine wire 9. The elastic modulus of the capillary material increases significantly at low temperatures, increasing the stiffness of the braided mesh and completing the grasping of the object.

[0029] The material of the capillary material thread 9 may be a shape memory polymer (SWP) or a thermoplastic elastomer (TPE).

[0030] Working principle: Figure 1 As shown, when stationary, the flexible braided net 1 is in an open position. When a clamped object is found, the driving wire 2 is pulled by the driving device to deform the flexible braided net 1. Different pulling forces are applied to the four driving wires 2, and the flexible braided net 1 will be deformed as shown in FIG. Figure 2 The contraction shown in the figure can effectively adapt to objects of different shapes, fit according to the shape of the object, and wrap the object. At this time, the variable stiffness capillary material wire 9 reduces the temperature by passing a cold medium to increase its own stiffness, ensuring a certain strength of gripping the object. After the grasped object is grasped and moved to the target position, the driving wire 2 can be loosened and a hot medium can be passed into the capillary material wire 9 to heat the variable stiffness wire for phase change. The strain energy of the ordinary wire can drive the grasping structure to return to the initial open state ( Figure 1 ) and release the grasped object.

[0031] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A thin sheet-like flexible braided gripper with variable stiffness, characterized in that: The invention comprises a flexible braided mesh (1), an end bracket (3), a plurality of drive wires (2), and a drive device. The center of the flexible braided mesh (1) is fixed on the end bracket (3), the drive wire (2) is placed in the flexible braided mesh (1), and the plurality of drive wires (2) are arranged in a circular manner with the end bracket (3) as the center. One end of the drive wire (2) is fixed to the outer edge of the flexible braided mesh (1), and the other end passes through the end bracket (3) and is connected to the drive device.

2. A thin sheet-like flexible braided gripper with variable stiffness according to claim 1, characterized in that: The flexible braided net (1) is formed by alternately braiding a plurality of transverse thin wires (7) and longitudinal thin wires (8); some of the transverse thin wires (7) or longitudinal thin wires (8) are capillary material thin wires (9) made of hollow capillary variable stiffness material; and two adjacent capillary material thin wires (9) are connected end to end via a silicone tube end joint (14).

3. A thin sheet-like flexible braided gripper with variable stiffness according to claim 2, characterized in that: It also includes a stiffness control device which can change the stiffness of the capillary material thread (9).

4. A thin sheet-like flexible braided gripper with variable stiffness according to claim 3, characterized in that: The stiffness control device comprises a hot medium source (10), a cold medium source (11), a liquid pump (12), and a recovery container (13); the hot medium source (10) and the cold medium source (11) are connected in parallel to the liquid inlet of the liquid pump (12); the outlet of the liquid pump (12) is connected to the head end inlet of the capillary material thread (9); and the tail end outlet of the capillary material thread (9) is connected to the recovery container (13).

5. The variable stiffness thin sheet-like flexible braided gripper according to claim 1, characterized in that: The end bracket (3) comprises a disc (6) and a screw (4); one side of the disc (6) has a boss to provide space for the movement of the gripper, and the other side is a buckle surface (5) for placing the screw (4); the flexible braided mesh (1) is installed in the buckle surface (5) via the screw (4).

6. A thin sheet-like flexible braided gripper with variable stiffness according to claim 2, characterized in that: The material of the capillary material thread (9) may be a shape memory polymer (SWP) or a thermoplastic elastomer (TPE).

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